Back to EveryPatent.com
United States Patent |
5,036,929
|
Trougouboff
|
August 6, 1991
|
Apparatus for handling heavy loads such as a trolley or a rolling chair
for the handicapped
Abstract
An apparatus for handling heavy loads, such as a wheelchair for the
handicapped, wherein a raising/lowering device is equipped with an
inclination sensor cooperating with a safety device for stopping the
device if a predetermined inclination is exceeded.
Inventors:
|
Trougouboff; Emile (15 bis, Avenue de Curti, Saint Maur des Fosses, FR)
|
Appl. No.:
|
490600 |
Filed:
|
May 21, 1990 |
PCT Filed:
|
July 28, 1989
|
PCT NO:
|
PCT/FR89/00399
|
371 Date:
|
May 21, 1990
|
102(e) Date:
|
May 21, 1990
|
PCT PUB.NO.:
|
WO90/00997 |
PCT PUB. Date:
|
February 8, 1990 |
Foreign Application Priority Data
Current U.S. Class: |
180/8.2; 180/282; 180/907; 280/5.22 |
Intern'l Class: |
B62B 005/02 |
Field of Search: |
414/921
180/8.2,282,907
280/5.22,5.28
|
References Cited
U.S. Patent Documents
2482203 | Sep., 1949 | Peterson et al. | 180/907.
|
2692652 | Oct., 1954 | Wilson | 180/282.
|
3231036 | Jan., 1966 | Appenrodt | 280/5.
|
3259202 | Jul., 1966 | Griffeth | 180/282.
|
3869011 | Mar., 1975 | Jensen | 280/5.
|
4109740 | Aug., 1978 | Andruchiw | 280/5.
|
4125169 | Nov., 1978 | Harris et al. | 180/907.
|
4222449 | Sep., 1980 | Feliz | 180/8.
|
4556229 | Dec., 1985 | Bihler et al. | 280/5.
|
4566707 | Jan., 1986 | Nitzberg | 280/5.
|
4674584 | Jun., 1987 | Watkins | 280/5.
|
Foreign Patent Documents |
1024367 | Feb., 1958 | DE | 280/5.
|
1405732 | May., 1969 | DE.
| |
1088980 | Mar., 1955 | FR.
| |
1533242 | Jul., 1968 | FR.
| |
2527155 | Nov., 1983 | FR.
| |
1230619 | May., 1971 | GB | 180/907.
|
2184988 | Jul., 1987 | GB | 180/907.
|
2188889 | Oct., 1987 | GB | 180/907.
|
Primary Examiner: Spar; Robert J.
Assistant Examiner: Katz; Robert S.
Attorney, Agent or Firm: Sandler, Greenblum & Bernstein
Claims
What is claimed is:
1. An apparatus for handling heavy loads, over discontinuous surfaces, said
apparatus comprising a step raising/lowering device comprising at least a
pair of endless chains, wherein each said chain further comprises at least
one stud which bears two coaxial and juxtaposed rollers located on either
side of said chain, said device further comprising an electric drive motor
for said raising/lowering device, that, in the course of operation said
drive motor drives said raising/lowering device, so that said
raising/lowering device, imparts to said apparatus a pivoting force about
a horizontal axis,
wherein said apparatus further comprises an inclination sensor for
detecting said apparatus inclination with respect to said horizontal axis,
and means for stopping said raising/lowering device, said means for
stopping being controlled by said sensor, when a predetermined inclination
with respect to said horizontal axis of said apparatus is exceeded.
2. An apparatus as claimed in claim 1, wherein said inclination sensor
comprises a movable element moving as a function of said apparatus
inclination with respect to said horizontal axis between a closed position
in contact with a set of electric contacts and an open position with said
set, said set of contacts being inserted in an electric power circuit
feeding said motor driving said raising/lowering device.
3. An apparatus as claimed in claim 2, wherein said sensor comprises a case
inside which said set of electric contacts is present at one end of the
path of said movable element, said case being affixed to said apparatus at
a predetermined inclination relative to a reference plane.
4. An apparatus as claimed in claim 3, wherein said case is mounted on a
support said support being mounted on said apparatus and rotatable about a
horizontal axis.
5. An apparatus as claimed in claim 4, wherein said support is a roller and
said inclination sensor comprises a mercury drop which is advantageously
placed inside a radial borehole in said roller.
6. An apparatus as claimed in claim 2 wherein said set of contacts is
present in said electric power supply circuit of said motor and in series
with a switch acting as the drive means of the raising/lowering device.
7. An apparatus as claimed in claim 1 wherein said apparatus is provided
with a stepping board and a front steerable wheel having a wheel axis of
rotation, said steerable wheel being mounted underneath said stepping
board and pivoting about an axis perpendicular to said wheel axis of
rotation, and wherein the pivoting motion of said wheel is manually
controlled and said wheel is driven in rotation by a separate motor,
wherein said apparatus further comprises an energy source which powers
said separate motor.
8. An apparatus as claimed in claim 7, wherein bearings of a drive shaft of
said steerable wheel are integrated into a set of supports which are
rigidly joined to a collar of controlled angular position mounted in a
rotatable manner underneath said stepping board, said drive motor for said
wheel being affixed to said collar.
9. An apparatus as claimed in claim 7, wherein a collar may be angularly
steered using cables, wherein said collar and said cables are adapted for
controlling said steerable wheel.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention concerns apparatus for handling heavy loads, such as a
hand-truck or a wheelchair for the handicapped, over a surface with
discontinuities such as steps. The invention is equipped with a
raising/lowering device on steps that comprises a motor driving the
raising/lowering device and during the operation of this device, forces
the apparatus to pivot about a horizontal axis.
2. Description of Background
Known apparatus of this kind as a rule will be operated by one person who,
when going up or down one or more steps of a staircase, keeps the
apparatus in an inclined position, advantageously near the equilibrium
position in order to lower the load the person is bearing. The
raising/lowering device in the known apparatus is located at the rear of
the apparatus' wheels, on the side of the person manoeuvering the chair.
When going up a staircase, these means tend to impart a forward pivoting
motion to the apparatus, that is, in the downward direction of the
staircase. Where a wheelchair for the handicapped is concerned, then the
handicapped person when seated in the chair is in danger falling.
SUMMARY OF THE INVENTION
The object of the present invention is to create an apparatus which shall
be free of these serious drawbacks.
To achieve this goal, the apparatus of the invention comprises an
apparatus-inclination sensor and a device for stopping the
raising/lowering means which is controlled by the sensor when a
predetermined inclination has been exceeded.
In one advantageous feature of the invention, the sensor comprises an
element inside a case and is movable between an open and a closed
electric-contact position as a function of the apparatus inclination, said
case being affixed to the apparatus at a predetermined slope relative to a
reference plane.
In another advantageous feature of the invention, the sensor is mounted in
a support on the apparatus rotatable about a horizontal axis in order to
allow changing the slope of the case.
In yet another feature of the invention, the above support is a roller and
the sensor is a mercury-drop inclination detector advantageously placed
inside a radial borehole in the roller, the borehole starting at the
roller's periphery.
DESCRIPTION OF DRAWINGS AND PREFERRED EMBODIMENTS
The invention and other purposes, features, details and advantages shall be
described further in the illustrative description below in relation to the
attached schematic drawings which are provided in purely didactic manner
and show an embodiment mode of the invention.
FIG. 1 is a schematic sideview of a wheelchair for handicapped, of the
known type, which is equipped with the systems of the invention,
FIG. 2 is a cutaway of the wheelchair of FIG. 1 in the direction of arrow
II,
FIG. 3 is a view on a larger scale and with cutaway of the detail denoted
by III in FIG. 1.
FIG. 4 is a sideview of the device shown in FIG. 3,
FIG. 5 is functional diagram of the power supply to the motor driving the
raising/lifting device of the invention, and
FIG. 6 is a schematic of a guidance system for the apparatus of the
invention.
FIG. 1 shows, as an illustrative example of apparatus for handling heavy
loads, a wheelchair 1 for the handicapped on a staircase. An assembly 2 in
the space underneath the seat houses a raising/lowering device denoted as
a whole by 3, a motor 4 driving the device 3 by a transmission means 5, a
storage battery 7 providing the electric power to the motor 4 and a case 8
enclosing both the electrical connections and the inclination sensor,
schematically indicated in FIG. 1 by 9.
It is further shown that the chair moves by means of two side wheels 10 at
bottom of the assembly 2 and by a steerable wheel 11 at the front of the
chair below the component 12 acting as stepping board, and between the
wheels 10. Each wheel 10 is associated with a step-edge detector
consisting of a roller 14 at the end of a pivoting arm 15. The step-edge
detector is capable of locking the wheel 10 against rotation when this arm
is beyond the edge 16 of a step.
The raising/lowering device 3, the transmission means 5 and the step-edge
sensor are known from the French patent number 2,527,155. The device 3
shall be described only briefly in relation to FIGS. 1 and 2.
By means of a transmission chain 18, the motor 4 drives into rotation a
shaft 17. The shaft 17 is horizontal in the chair frame, approximately at
the level of the axles of the wheels 10 but is offset to the rear as shown
by FIG. 1. On each side of the chair the shaft 17 drives an endless chain
19 which at the upper part winds around a pinion on a shaft 20 parallel to
but above the shaft 17, inside the assembly 2. Two studs 22 each bearing
two coaxial and juxtaposed rollers 23, located on either side of the chain
19, are mounted at equal distance on each chain. The studs 22 project to
the outside in such a way that the rollers can come to rest against the
fore part of a step. As shown by FIG. 1 in this respect, when the chains
move in the direction indicated by the arrow F1, the rollers 23, resting
against the step, cause the chair to rise. Similarly, when the rollers
rest on the step and the chains move in the inverse direction of the arrow
F1, the chair shall descend. In the course of such ascending or descending
motion of the chair, and considering that the chair's center of gravity
does not coincide with the axis of the rollers, this chair would pivot
about rollers 23 if the chair were not held in a suitably inclined
position by the person handling the chair, in the manner known per se.
When the raising/lowering device causes the chair to ascend with the
chains 19 moving in the direction of the arrow F1, the chair shall be
subjected to a torque tending to pivot it in the direction of the arrow
F2.
The present invention concerns means for averting accidents from the
above-noted pivoting by stopping the raising/lowering device when the
inclination of the wheelchair exceeds a predetermined angle. These means
include an inclination sensor 9 which is stationary on the wheelchair, for
instance inside the case 8, in the manner shown in FIG. 1. In the
illustrative embodiment shown in the Figures, the inclination sensor is a
mercury drop type sensor. This sensor comprises an oblong ampule 25 having
at one end two electric contacts 26, 27 and inside which is a mercury drop
28. This drop moves inside the ampule between a position away from the
contacts 26, 27 as shown in FIG. 3 by the dash lines being at a, and a
contact-closing position, shown in solid lines, at b. In the example shown
by FIGS. 3 and 4, the ampule 25 is located within a suitable radial
borehole in a roller 28 beginning at the roller periphery. This roller 28
is mounted so as to allow angular variation, on the inside fixed wall of
the case 8, around a horizontal axis. In FIG. 4, 29 denotes means for
locking the roller 28 into a predetermined angular position.
As shown in FIG. 5, it will be noted that the contacts 26, 27 are in series
with a switch 30 actuated by the person moving the wheelchair, and with
the electric power circuit of the motor 4 for driving the raising/lowering
device 3 by means of the battery 7. In the electric diagram shown, once
the inclination of the wheelchair 1 exceeds a predetermined value
corresponding to the horizontal line 31 of FIG. 3, the contact between the
elements 26, 27 of the sensor 3--which normally is closed--will open, so
that the power to the motor 4 is shut off. Thus, the raising/lowering
device 3 is stopped regardless of the position of the switch 30, that is,
even if the person operating the wheelchair keeps this contact closed. It
is easily seen that as a result, in light of the stoppage of the
raising/lowering device, the pivoting motion--which might not be
controlled by the person operating the wheelchair--has been stopped.
To program the inclination angle .alpha. of the wheelchair 1 at which the
inclination sensor 9 must stop the motor 4, the wheelchair is placed at
that inclination and the roller 28 is made to rotate until the axis of the
ampule 25 coincides with the horizontal line 31.
FIG. 6 schematically shows another feature of the present invention,
allowing control of the front wheel 11 steering. This wheel 11 is rigidly
joined to a shaft 32, which rotates in supports 33, themselves fixed
underneath a collar 34, which rotates underneath the wheelchair
stepping-board 12 about an axis perpendicular to the plane of the stepping
board. The collar 34 also supports a motor 35, for instance an electric
motor, which may be powered from the battery 7. This motor is arranged in
such a way that it can drive the shaft 32 into rotation. This shaft 32 may
be the output shaft of the motor 35. At its periphery, the collar 34 is
provided with one or more peripheral grooves through which passes a cable
36, so that by pulling on either of the two ends of cable 36, the collar
shall rotate in either direction. The ends of the cable 36 may be affixed
to manual control means illustratively located at the level of the
wheelchair armrests so that the wheelchair user himself can control the
orientation of the wheel 11. Where called for, the user also has access to
the control means for the wheel 11.
Obviously many modifications may be introduced in the above described
wheelchair without thereby transcending the scope of the invention.
Illustratively the inclination detector might of any other suitable and
known species.
Top